Various cleaning articles have been created for dusting and light cleaning. For example, cloth rags and paper towels used dry or wetted with polishing and cleaning compositions have been used on relatively flat surfaces such as countertops, showers, sinks and floors. Laminiferous wipes have been proposed, as disclosed in U.S. Pat. No. 9,296,176. But, rags, wipes, and paper towels are problematic for reasons such as hygiene (the user's hands may touch chemicals, dirt or the surface during cleaning), reach (it may be difficult to insert the user's hand with the rag, wipe or paper towel into hard-to-reach places) and inconvenience (cleaning between closely-spaced articles typically requires moving the articles).
To overcome the problems associated with using rags and paper towels, various reusable dust gathering devices using felt and hair have been utilized for more than a century, as illustrated by U.S. Pat. No. 823,725 issued in 1906 to Hayden and using yarns as illustrated in U.S. Pat. No. 4,145,787. To address the problems with reusable dust gathering devices, disposable cleaning articles have been developed which have limited re-usability. These disposable cleaning articles may include synthetic fiber tufts, called tow fibers, attached to a sheet as shown in 2006/0171764; U.S. Pat. Nos. 6,143,393; 6,241,835; 6,319,593; 6,329,308; 6,554,937; 6,774,070; 6,813,801; 6,830,801; 6,984,615; 7,003,856; 7,566,671; 7,712,178; 7,779,502; 7,870,635; 7,937,797; 8,146,197; 8,151,402; 8,161,594, 8,186,001; 8,225,453; 8,245,349; 8,646,144; 8,528,151; 8,617,685; 8,646,144; 8,752,232; 8,756,746; 8,763,197; 8,793,832; 9,113,768; 9,198,553 and in commonly assigned U.S. Pat. No. 8,075,977.
Disposable dusters having tow fibers may provide for wet cleaning as disclosed in U.S. Pat. No. 7,566,671 and in commonly assigned U.S. Pat. No. 7,803,726 and commonly assigned US 2008/0028560. But tow fibers may become matted when wet and not be suitable for cleaning a large or heavily wetted surface, such as a floor. Thus, dusters may not suitable for cleaning extremely large or heavily soiled surfaces.
Thus various sheets have been proposed for cleaning larger target surfaces, such as floors. Webs with elastic behavior have been proposed in commonly assigned U.S. Pat. No. 5,691,035. Sheets with recesses have also been proposed, as disclosed in U.S. Pat. Nos. 6,245,413; and 7,386,907. Sheets with cavities have been proposed, as disclosed in U.S. Pat. No. 6,550,092. An adhesive cleaning sheet is proposed in U.S. Pat. No. 7,291,359. Tufts are taught in commonly assigned U.S. Pat. Nos. 7,682,686, 7,838,099 and/or 8,075,977. Yet other attempts use coatings of wax and/or oil. Coatings, such as wax and oil are generally disclosed in U.S. Pat. Nos. 6,550,092; 6,777,064; 6,797,357; 6,936,330; 6,984,615; 7,386,907; 7,560,398; 7,786,030; 8,536,074; 9,204,775; 9,339,165. Specific amphiphilic coatings are disclosed in U.S. Pat. No. 8,851,776.
Some of the prior art attempted to focus on debris as simply large and small, based upon the size of the debris intended to be collected. But these teachings do not always address the proper use of tow fibers to collect the range of debris commonly found when cleaning a floor. Dense, granular debris, such as dirt, is not necessarily captured by tow fibers. Low density, more voluminous debris, such as hair, is not necessarily captured by nonwovens. Prior art attempts to incorporate tow fibers into cleaning sheets did not account for such differences in volume and density. Tow fibers which are too closely spaced may not intercept and hold the more voluminous, lower density debris. Tow fibers which are spaced too far apart may not even come in contact with dense, granular debris—much less clean such debris from the surface. Even if such debris is initially captured, prior art sheets have not addressed the problem of how to retain such debris by the sheet.
Accordingly, this invention addresses the problem of how to incorporate tow fibers into a hard surface cleaning article for capture and retention of the wide range of debris encountered in everyday cleaning by through the preferential placement of tow tufts on a cleaning sheet.